

  document.addEventListener( 'mousemove', onDocumentMouseMove, false );


	function onWindowResize() {

	windowHalfX = window.innerWidth / 2;
	windowHalfY = window.innerHeight / 2;

	camera.aspect = window.innerWidth / window.innerHeight;
	camera.updateProjectionMatrix();

	renderer.setSize( window.innerWidth, window.innerHeight );

	}
  



	function onDocumentMouseMove(event) {

		mouseX = ( event.clientX - windowHalfX );
		mouseY = ( event.clientY - windowHalfY );

	}